Evaluation of the Safety and Ochratoxin A Degradation Capacity of Pediococcus pentosaceus as a Dietary Probiotic with Molecular Docking Approach and Pharmacokinetic Toxicity Assessment

Abstract

The present study evaluated the properties and ochratoxin A (OTA) degradation capacity of the dietary probiotic Pediococcus pentosaceus BalaMMB-P3, isolated from a milk coagulant. The acidic tolerance of the isolate at pH 2-3 was checked with bile salts. No hemolytic activity was noted, which confirmed the nonpathogenicity of the strain. The isolate was tested in vitro for antibiotic susceptibility, enzymatic activity, bile salts hydrolase activity and antifungal activity against Penicillium verrucosum, Fusarium graminearum and Aspergillus ochraceus. A molecular docking-based OTA toxicity assessment was carried out for multitargeted proteins. The 16S rRNA gene-based phylogenetic assessment identified the strain as P. pentosaceus, and was authenticated in GenBank. The carboxylesterase and glutathione s-transferase enzymes showed active and strong interactions with esters and amide bonds, respectively. The compound exhibited carcinogenic and cytotoxicity effects at an LD₅₀ value of 20 mg/kg. Furthermore, the strain showed a potent ability to reduce OTA and suggested the prospects for utilization in nutritional aspects of food.

Keywords: Pediococcus sp.; biodetoxification; ochratoxin A; probiotics; toxicity assessment.

Figure 1

Phylogenetic tree based on 16S rDNA gene sequence showing the relationship between Pediococcus strains and species belonging to the genus Pediococcus. The highlighted red box indicated the species identified in the study.

Figure 2

pH-resistant properties and survival ability at different pH and bile salt levels. Analysis was conducted in triplicate (n = 3).

Figure 3

Antifungal activity of P. pentosaceus against A. ochraceus (a), P. verrucosum (b) and F. graminearum (c).

Figure 4

Hemolytic activity of P. pentosaceus BalaMMB-P3.

Figure 5

Enzymatic activities of P. pentosaceus in lipase agar (a), amylase agar (b) and protease agar (c).

Figure 6

The OTA degradation (a) 0.8 ppm of OTA in MRS, (b) control (Pediococcus pentosaceus in MRS without OTA) and (c) MRS after the incubation with P. pentosaceus and 0.8 ppm of OTA for 24 h.

Figure 7

The molecular structure of OTA, the amide bond, ester, Cl and epoxide moiety at the site of detoxification.

Figure 8

The docked complex molecule of carboxylesterase showing pocket binding sites (A), three-dimensional structure of interaction (B) and two-dimensional interaction diagram (C). This enzyme interacted with the ester molecule of the ochratoxin compound, which could be a possible site for degradation or detoxification mechanisms.

Figure 9

The docked complex molecule of glutathione s-transferase shows 3D pocket binding sites (A), the three-dimensional structure of molecular interactions (B) and the two-dimensional interaction diagram (C). These enzymes interacted with the amide bond and epoxide moiety of the ochratoxin compound, which could be a possible site for degradation or detoxification mechanisms.